After a cagey opening half with few clear chances, Mateta turned in a rebound for the game’s only goal on 51 minutes, sending departing coach Oliver Glasner off in style.
Glasner departs with a third trophy in two years as Palace manager, the most successful period in the club’s history, after dashing Rayo’s hopes of landing their first major silverware.
“The difference he (Glasner) has made in two and a half years is incredible,” Palace midfielder Adam Wharton told TNT Sports.
“Three trophies, the first in the history of the club, first European competition and winning it.
“He’s got to be one of the best managers Palace have had and he’s made a huge difference to how the club looks at competitions now. We’re looking to win it.”
The victory also completed Glasner’s objective of returning Palace to the Europa League, the competition they qualified to play in this season before falling foul of multi-club ownership rules and being demoted to the Conference League.
The Austrian, already a Europa League champion with Eintracht Frankfurt in 2022, once again showed his excellence in knockout competitions.
Palace overcame the sales of star players Eberechi Eze and Marc Guehi this season, and the fallout from the latter’s January move to Manchester City, to cap their first full venture into European competition with a title.
France striker Mateta, the hero on the night, was a failed medical away from leaving Palace for AC Milan this winter.
“I feel fantastic,” said Mateta. “First time in Europe, we did it! Now I just want to celebrate, I just want to party.
“I’m tired, man. I gave everything. The team gave everything and that’s why we won today.”
Palace became third London side in as many years to win the competition, after West Ham in 2024 and Chelsea in 2025, demonstrating the Premier League’s unmatched financial muscle.
With Aston Villa already Europa League winners, Premier League champions Arsenal can complete a clean sweep in European competition by beating Paris Saint-Germain in the Champions League final on Saturday. (AFP)